How Sustainable Is Recycled Polyester? 

May 25, 2023

Recycling plastic is just one way humanity is trying to undo the havoc it has wreaked on the environment. And now textile recycling has emerged as a new type of recycling aimed to reduce the use of raw materials and textile waste.

One material that manufacturers have begun to include in textile-to-textile recycling is polyester fabric. Ubiquitous in the fashion industry, the production of new polyester is pretty terrible for the environment. 

Is recycled polyester a true green alternative?

Let’s Talk About Polyester

Before diving into what recycled polyester is, it’s worth having a look at polyester itself. A synthetic fabric, it’s been used to make clothes and similar products for nearly a century. Polyester originally gained popularity because of its versatility and durability, as well as being inexpensive to produce.

As climate change worsens, the average consumer becomes more conscious of the ecological impact of their choices, looking for ways to be more sustainable and reduce waste. That involves a closer look at polyester’s environmental impact. Polyester is one of the least eco-friendly textiles to choose from, affecting the environment in a number of harmful ways.

Fossil fuels

Polyester is made with ethylene glycol and terephthalic acid, both of which are derived from fossil fuels such as gas, coal, and petroleum, raw materials removed from deep within the earth. Indeed, according to the Changing Markets Foundation, “the textile industry currently accounts for 1.35% of global oil consumption.” 

The obtaining, producing, and burning of these materials contributes to the worsening climate crisis. The emission of greenhouse gases from the production of synthetic fibers is six times worse than that of natural fabrics, such as cotton or rayon. Unlike polyester, those fabrics use renewable resources—trees and plants—to create textiles.

Nonbiodegradable textile waste

Consumers throw away clothes at destructive rates, with the amount of textile waste by Americans doubling over the last 20 years. According to the EPA, a shocking 84% of these discarded textiles end up in one landfill or another, where they can take up to 200 years to biodegrade. As a synthetic fabric made from plastic, polyester is one of the worst offenders. 

While these materials sit in landfills, they release the greenhouse gas methane into the atmosphere and toxic chemicals and artificial dyes into the soil and groundwater.

Microplastics

Polyester releases microplastics into the environment when it is washed, when it is worn, and when it is thrown away. Microplastics are pieces of plastic waste that are five millimeters or less in length, and these tiny plastic fibers are eaten by fish, causing complications in their digestive systems, causing death, or entering the greater food chain, including humans. A whopping 73% of fish caught in the northwest Atlantic have microplastics in their digestive system. Microplastics have been found in 114 aquatic species, making it a widespread ecological problem. Drinking water alone accounts for 1,769 particles of microplastics consumed by the average human each week.

Current estimates claim that 496,030 pieces of microplastic are released for every 6 kg of polyester with every wash. In practical terms, that’s a population of 100,000 people generating 1.02 kg of microfibers per day, which equates to 793 pounds per person per year.

While there’s no way to prevent the release of microplastics during a wash, there are ways to minimize it:

  • Limit the amount of washes done
  • Wash at lower temperatures, which is proven to release fewer microplastics
  • Instal microfiber filters or similar products that catch microplastics before they reach the environment

What Is Recycled Polyester?

As the name suggests, recycled polyester, also known as rPET or recycled polyethylene terephthalate, is made from recycled plastics, although the surprising part is that the source of this isn’t solely polyester itself. Instead, it’s made from recycled plastic bottles and other recycled materials. Its main component is polyethylene terephthalate, which is found in every polyester product.

The fabric takes these products and puts them through one of two recycling processes before being made into polyester clothing. As few as five water bottles have enough fibers to create an extra-large T-shirt.

Recycled polyester garments aren’t the perfect solution they seem to be, though. Despite the apparent environmental friendliness of this, it has its drawbacks. It’s worth looking at the pros and cons of recycled polyester to determine whether it’s as sustainable as the name suggests.

Pros

Recycled polyester’s apparent sustainability is its main attraction because it prevents plastics from going to a landfill or body of water. With eight million metric tonnes of plastic water bottles and other trash making its way into the ocean every year, the wide adoption of rPET could minimize, if not remove, the harmful environmental impact this has. Should recycled polyester usage outpace plastic production, it could also go a long way to removing the approximately 150 million metric tonnes currently circulating in marine environments. The same could be said for plastic that gets thrown away, with over 27 million tonnes of plastic being sent to landfills every year in the United States alone.

Because polyester is made from plastic, recycled polyester requires less reliance on the extraction of crude oil and petroleum to create the material, which eliminates the environmental concerns associated with the extraction of fossil fuels, at least where polyester is concerned. 

As far as quality goes, rPET recycled material has the same quality as its conventional counterpart, although it needs 59% of the resources and emits 32% fewer carbon emissions than regular polyester.

Cons

Recycled polyester doesn’t come without its drawbacks, however, with critics highlighting that products containing polyester—predominantly clothes—are difficult to recycle, as they’re typically blended with another fabric. While fabrics such as cotton are recyclable alongside the polyester, the process behind recycling two fabrics blended together is still in its infancy and will take time before it can scale up manufacturing.

Even if a product is 100% polyester, recycling it comes with its own complications. For example, each time it’s recycled, the fabric degrades in quality. Eventually, it may no longer be fit for repurposing.

Using recycled clothing could also lead to some inverse logic among consumers. Once they know that more and more materials are recyclable, especially plastics, they may use more of these products, which might then increase consumption, rather than reduce it. Overconsumption is at the heart of humanity’s devastating impact on the environment.

How Is Recycled Polyester Made?

Recycled polyester is made in two ways: chemical recycling and mechanical recycling. With the mechanical manufacturing process, plastic bottles and similar items are shredded into flakes and melted to make a new yarn. Mechanical recycling accounts for most rPET because it is cheaper than chemical recycling and doesn’t use any toxic chemicals.

The chemical manufacturing recycling process, as the name suggests, uses a chemical process to break down the plastic. While the chemicals in this recycling process may be concerning, brands like outdoor clothing manufacturer Patagonia use an eco-friendly process and boast that their process produces 35% fewer carbon emissions compared to traditional polyester. The process also maintains the fabric’s quality, increasing its longevity and potentially lessening its environmental impact.

After either chemical recycling or mechanical recycling, the material goes through a melting process and is then spun into yarn, becoming a fiber and then a fabric, after which it’s made into a new product.

What are the properties of recycled polyester?

Recycled polyester boasts many of the same properties as its traditional counterpart, making it an ideal alternative to traditional polyester. Studies show that the production of rPET doesn’t hurt its quality in a significant manner, making it as durable, long lasting, and strong as polyester. It’s notable, however, that rPET becomes more rigid over time, with estimates claiming recycled polyester is 9% to 26% stiffer than its non-recycled counterpart, and it appears to worsen over time. Outside of that, rPET is known to be flame retardant and resistant to heat, impact, and tears, adding to its durability.

What Is Recycled Polyester Used For?

As it has the same properties as traditional polyester, rPET is used in all of the same types of products, namely, outdoor garments, T-shirts, activewear, loungewear, and other clothing. It’s not as widely available as its non-recycled counterpart, however, and is typically blended with another fabric when being turned into a finished product. Even shoes, bags, and other accessories can be made from recycled polyester.

Because of the above properties, multiple sustainable fashion brands have begun using recycled polyester in their products:

Is Recycled Polyester Environmentally Friendly?

Whether the use of recycled polyester is environmentally friendly is debatable. While it does extend the lifespan of plastic products, recycled polyester requires the production of virgin PET (polyethylene terephthalate). You can’t recycle plastic if plastic isn’t produced in the first place. With how harmful plastic production is to the environment, anything made of plastics can’t be overly environmentally friendly.

Furthermore, dye and chlorine bleach are applied to rPET during the recycling process, as well as water and energy, especially with larger brands that mass-produce products. These chemicals can have a harmful impact on the environment, unless made in a sustainable manner. Though less energy and water are needed to make rPET compared to non-recycled polyester, the energy it uses still has an impact.

And at the end of the day, even recycled polyester isn’t biodegradable. It will eventually end up in a landfill, just not as soon, perhaps.

Still, recycled polyester fans highlight its multiple environmental benefits. It removes waste from oceans and dumps and will eventually lead to less fossil fuel extraction, or that’s the idea anyway.

Compared to fabrics made from sustainable materials, however, the use of recycled polyester clothing isn’t as eco-friendly as consumers may hope.

How Does rPET Compare to Other Materials?

Recycled polyester can be compared to multiple fabrics, with its non-recycled counterpart being the most obvious. Both of these are identical in almost every way, aside from the slightly increased sustainability associated with rPET. But how does it stand up against others on the textile exchange?

Nylon

Recycled polyester and nylon are quite similar to polyester, with nylon being the softer, lighter, and silkier fabric. While both fabrics are used in many of the same ways—clothes, housewares, etc.—nylon is more expensive than polyester and less widely available, although rPET appears to be harder to find still.

Despite this, these textiles have similar properties, with both offering roughly the same breathability, durability, flammability, and weather resistance. As they’re both synthetics, it appears that they cause similar harm to the environment, with nylon languishing text to polyester in every landfill, although both fabrics have brands that aim to minimize or remove this effect.

Organic cotton

Organic cotton and recycled polyester are at practically opposite ends of the sustainability spectrum. There are countless differences between the two in almost every category. The only apparent similarities between organic cotton and recycled polyester are that they can be put to the same uses, such as providing the world’s clothing.

Organic cotton, however, is the much more eco-friendly option. It’s made from a natural material, it’s biodegradable, and it has a much smaller impact on the environment. The differences between organic cotton and polyester extend to the feel of the fabrics, with organic cotton being softer and feeling silky to the touch. Organic cotton is also more breathable and absorbent than polyester. 

Rayon

Rayon is a family of fabrics comprising modal, viscose, and lyocell fabric, each boasting similar properties, but lyocell is the most environmentally friendly of the three.

There are numerous differences between rayon and recycled polyester. For example, rayon fabrics are softer and have a silkier feel. They also appear to be more sustainable than rPET, thanks to being semisynthetic and using a closed-loop system to prevent toxic chemicals from polluting local ecosystems. Rayon fabrics are partly made from natural materials that can be grown and harvested in eco-friendly ways. The same can’t be said for recycled polyester’s base material—plastic.

There are also multiple differences in properties. Rayon is less durable than polyester, less water resistant, and more prone to wrinkling. Despite this, recycled polyester and rayons have some similarities, such as being vegan and retaining heat well. As such, they’re both used in many of the same products, such as clothing.

Conclusion

Recycled polyester lessens the amount of plastic in landfills and oceans and could lessen carbon emissions if used widely, making it a more sustainable option than other synthetic materials.

Despite this, it still relies on plastic production. It’s more a stopgap solution to making fashion and other areas more environmentally friendly—a Band-aid on an open wound.